In an existing Long Term Evolution (LTE) technology, when a terminal in an Evolved Mobility Management (EMM)-DEREGISTERED state is expected to return to an EMM-REGISTERED state, the terminal may initiate an attach flow, and the flow is a Non-Access Stratum (NAS) flow. For example, upon the terminal starts or a Subscriber Identity Module (SIM) card is inserted into the terminal, the terminal will return to the EMM-REGISTERED state from the EMM-DEREGISTERED state, and requires the attach procedure. The attach procedure is born on an Access Stratum (AS) procedure. That is, an AS is required to complete downlink synchronization, random access and connection establishment at first, and then interaction about signaling such as an attach REQUEST, attach ACCEPT and attach COMPLETE is performed through NAS signaling.
An existing LTE system is discussing introduction of an LTE-technology-based Vehicle to X (V2X) system. Here, a mobile terminal is a running vehicle which is different from a conventional terminal such as a mobile phone or a computer. A behavior pattern of an automobile is different from an ordinary terminal. That is to say, most of automobiles run for a limited time period each day. The powering-on and powering-off frequency of an automobile is far higher than a conventional terminal. Registration/deregistration management is required to be performed on an automobile type terminal by adopting a conventional attach/detach manner every time. For example, when an owner drives an automobile to a place such as a post office, a supermarket and a shopping mall with a short stay, a detach/attach procedure is required to be performed on the automobile. In another example, the owner waits for another passenger by the roadside in the automobile with the automobile temporarily powered off, a detach/attach procedure is required to be performed on the automobile.
From the above scenarios, it can be seen that an existing attach/detach procedure may be used for an LTE-technology-based V2X system. That is, in a manner similar to that of an existing terminal, attach is performed when a vehicle is started and detach is performed when the vehicle is stopped. However, the vehicle is powered off and powered on relatively frequently. If a conventional attach/detach manner is still adopted for registration/deregistration management over a vehicle type terminal, a lot of signaling may be unnecessarily wasted. Moreover, a first starting access latency of the vehicle may be influenced.